Mining machine having cutter chain slack take-up means



Aug. 26, 1958 Re. 24,523

MINING MACI-IINE-HI WING' CUTTER CHAIN SLACK TAKE-UP MEANS J. 5. ROBBINS 3 Sheets-Sheet 1 Original Filed Jan..4, I952 m T ow wv NY 2 v mm JAMES S. ROBBINS Aug. 26 1958 Original Filed Jan. 4, 1952 FIG.

J. 5. ROBBINS Re. 24,523 MINING MACHINE HAVING CUTTER CHAIN SLACK TAKE-UP-MEANS 3 Sheets-Sheet 2 llllllll.

MINING MACHINE HAVING CUTTER CHAIN SLACK TAKE-UP MEANS Aug; 26, 1958 J. 5. ROBBINS 3 Sheets-Sheet 3 Original Filed Jan. 4, 1952 JAMES S. ROBBINS United States Patent Ofiice Re. 24,523 Reissued Aug. 26, 1958 MINING MACHINE HAVING CUTTER CHAIN SLACK TAKE-UP MEANS James S. Robbins, Seattle, Wash, assignor to Goodman Manufacturing Company, Chicago, 111., a corporation of Illinois Original No. 2,743,093, dated April 24, 1956, Serial No. 440,375, June 30, 1954, which is a division of Serial No. 264,880, January 4, 1952, now Patent No. 2,705,624, dated April 5, 1955. Application for reissue March 24, 1958, Serial No. 723,619

5 Claims. (Cl. 262-7) Matter enclosed in heavy brackets appears in the original patent but forms no part of this reissue specification; matter printed in italics indicates the additions made by reissue.

This invention relates generally to mining machines of the [general] continuous type having a pair of boring arms for cutting a pair of overlapping contiguous bores in a seam of coal or the like, and particularly to a slack take-up device for the endless cutter chains for cutting the [cores] cusps resulting from the action of the boring arms in cutting such overlapping bores.

One of the principal objects of this invention is to provide a simple slack take-up device for the upper and lower cutter chains, particularly when the guides therefor are retracted.

A further object of this invention is to provide a con- .tinuous type mining machine with a slack take-up device for the cutter chains which will maintain and control the amount of looseness or slack in the cutter chains during the movement of the cutter chain guides.

A still further object of this invention is to provide a tensioning means for the cutter chains of a continuous type mining machine for imposing the proper amount of tightness or tension in the cutter chains.

Another object of this invention is to provide a mining machine, of the type described, with a slack take-up device and tensioning means for maintaining and controlling the looseness or slack and imposing the proper amount of tightness or tension to an endless cutter chain during the movement of the cutter chain guide.

Other objects and important features of the invention will be apparent from a study of the following'specification taken with the drawings, which together show a preferred embodiment of the invention and what is now considered to be the best mode of practicing the principles thereof. Other embodiments of the invention may be suggested to those having the benefit of the teachings herein, and it is therefore intended that the scope of the invention not be limited by the precise embodiment herein shown and described, such other embodiments being intended to be reserved especially as they fall within the scope and purview of the subjoined claims.

In the drawings:

Fig. 1 is a partial side elevation view of a continuous miner having embodied therein the improvements according to the present invention, said view being adjacent the forward portions of the machine only; I

Fig. 2 is a front elevation view of the machine shown in Fig. 1 said view being taken in the direction of the arrows 22 of Fig. 1; and

Fig. 3 is a front elevation view taken along the line 33 of Fig. 1 and looking in the direction of the arrows, showing the upper and lower chain guides and the endless cutter chains arranged to move on said guides, and the slack take-up devices and tensioning means therefor forming the improvement on the machine of the [general] continuous type referred to herein.

Referring now particularly to Fig. 1 of the drawings, there is shown the forward portion of a continuous miner indicated generally by the reference numeral 10. Such a miner includes a main frame 11 mounted for movement upon a pair of endless crawler treads 12. The main frame 11 forms a support for a[n auxiliary frame and] drive housing 13 and includes an auxiliary frame which is mounted for up and down movement in a vertical direction with respect to the mainframe 11 by means of lifting cylinders 14. Other cylinders, not shown, are arranged to give tilting movement to the housing in vertical plane so as to accommodate pitching of a seam of coal or the like.

The drive housing 13 includes a pair of laterally spaced gear housings 16 and 17 which respectively have'extend ing therefrom drive shafts 18 and 19 for a pair of boring arms 21 and 22, see also Fig. 2. [Boring] The boring arms 21 and 22 are driven in timed relationship in opposite directions by means of a gear train contained within the drive housing 13 and the spaced gear housings 16 and 17.

The aforesaid action of the boring arms 21 and 22 in cutting a pair of overlapping contiguous bores leaves behind an upper [core] cusp and a lower [core] cusp. In order to remove the [cores]'cusps resulting from the action of the boring arms 21 and 22 endless cutter chains 30 and 55 are provided [having] which have a path of travel to the rear of the boring arms, as seen in Figs. 1 and 3.

To this end, see particularly Fig. 3, there is provided a channel-shaped upper cutter chain guide 27 having an idler sprocket or shoe 28 mounted at the left end thereof and a similar idler sprocket or shoe 29 mounted at the right end thereof. [An] The endless cutter chain 30 is arranged to travel in the guide 27 and is driven by a driving sprocket 31 mounted on a shaft 32 extending from a front wall of the drive housing 13. The endless chain 30 is additionally trained about an idler member, such as a shoe or sprocket 34, arranged under conditions, as will appear as this specification proceeds, to move in a partially orbital fashion with respect to the driving sprocket 31 [so as] to [at all times] take up the slack in the endless cutter chain 30 and to impose the proper amount of tension thereon at all times.

[Cutter] The cutter chain guide 27 is arranged to be moved vertically by means of a pair of laterally spaced lifting cylinders 36, 36 which are mounted on the [forward] front wall of the drive housing 13, and behind the plane of the boring arms 21, 22, as seen in Fig. 2. Each of the cylinders 36 has a piston rod 37 which is connected by a pin 38 to the upper chain guide 27, see Fig. 3.

As seen in Fig. 3, there is also provided a similar channel-shaped lower chain guide [38] 40 which is arranged to cut the lower [core] cusp remaining from the action of the boring arms 21, 22. The lower cutter chain guide [38] 40 has mounted at the left end thereof an idler sprocket or shoe 39, and the right end thereof has a similar idler sprocket or shoe 41. The two shoes or sprockets 39 and 41 are each mounted on rock arms 42 and pivoted at 43 to the guide [38] 40. These rock arms 42 are arranged to be rocked to a collapsed position, as [seen] illustrated in dot-dash lines in the right hand part of Fig. 3, by means of [a] cylinders 44 which [is] are each connected pivotally at 46 to a downward extension 47 from the drive housing 13. [The] Each of the cylinders 44 has a piston rod 48 which is connected to the point of hinged connection 50 of a pair of links 49 and 51, link 49 being pivotally connected at 52 to the rock arm 42 and the link 51 being pivotally connected at 53 to a bracket 54 extendng from each gear [casing] housing 16 and 17. 7

As seen with respect to Fig. 3, the. idler sprockets .or.

shoes 39 and 41 are arranged to be rocked to collapsed position when fluid is admitted to the cylinders 44, the two links 49 and 51- ten-ding. to form an acute'ranglexwith respect to each other during such [applicationzl'adm-ission of fluid to the cylinders 44.

[An] The endless-chain 55 is trainedaround. thenslroes;

39,41 and across the lower guide [38] 40 and iaboutca' and isarranged to take up and maintain the slack constant.

and to impose the proper tension upon the endless chain The two idler [sprockets] members 34 and 58 which are arranged to move in a [partial obital] partially orbital.

fashion with respect to their respective driving sprockets 31 and 56 will now be described. The description [obtaining] for the idler [sprocket] member 58 and its support about the driving sprocket 56 will sufli-ce also.

for the idler [sprocket] member 34, and so the description for the idler [sprocket] member 34 will not be repeated.

The idler [sprocket] member 58 is accordingly mounted upon an arm 59 having a center corresponding to'the center of the shaft 57. The arm 59 is also pro-. vided with aguia'ein the form of an arcuate surface .61 which'is substantially coincident with the path of travel or swinging movement of the idler member 58 in the partially orbital fashion about the driving sprocket 56 and 'a'flexible strand 62 is anchored at one end to a stub shaft 63 supporting the idler [sprocket] member 58'.

upon the arm 59. The flexible strand 62 is connected at its other end to arod 64 encircled by a spring 66 which l aimia my e ti m 1. In a mining machine of the type having a pair of boringarms arranged to cutcontiguous bores[in a-seam of coal or the like], at least one retractable cutter chain guide and an endless cutter chain guided thereby for cutting a cusp remaining from the action of said boring arms, and a driving sprocket for said cutter chain, the improvement insuchminingmach-ine which comprises: means for taking up [the] "slack in said cutter chain occasioned by movement of said cutter chain guide to retracted' position comprising an idler sprocket, an armsupporting said idler sprocket and mounted for swinging is adjusted in tension by adjusting nuts 67. One. end of the spring 66 abuts a washer 68 bearing against theadjusting nuts 67 and the other end of the spring is bottomed in an essentially 'U-shaped stirrup 69 which is secured as by Welding to the [forward] front wall of the drive housing 13.

When it is desired to" remove the machine 10 from, [the] a location or room'in which it operates, the upper, cutter chain guide 27 is retracted by means of the cylin-..

ders 36, 36. The shoes 39'and 41 at the lower cutter chain guide [38] are likewise retracted by means of.

the cylinders 44, 44. Ordinarily the entire boring means and the lower chain guide may be lifted from the mine floor by means of "thelifting cylinders 14, as seen in Fig. 1.

Upon such movement ofthe upper cutter chain [bar] guide 27 and the rock arms 42', 42, the idler sprockets 34 and 58 will be urged by the spring 66, which normally tends to elongate, to rock the two idler [sprockets] members 34 and 58 in a counter-clockwise direction with 'respect to' their associated driving sprockets 31 and '56, thereby storing, tensioning and/ or taking up the slack in the chain during such retraction of the machine.

From the foregoing description it is believed andreadily, understood that a simple means has been. provided foit taking up slack in the cutter chains [as may be] ,occasioned by retraction of the upper cutter chain [bar] guide and the lower cutter chain [bar] guide, the take-up being additionally characterized by imposing at all times.v

the proper amount of tension upon the chain.

This application is a division of my ,copendingsappli cation Serial No. 264,880, filed January 4, 1952,. for Coal Mining Machines, now Patent vNo. 2,705,624.

While the invention has been described in, termsof-a preferred embodiment thereof it is intended that the scope thereof be limited only by the terms of the claims here appended.

movement[, said arm having its] about a center of swinginglmovement corresponding to-the center of rotation of saiddriving sprocket,-a guide upon said arm, said gu1de and wrapped along said arcuate surface, and a spring con-' nected at one end to said strand-and at the other end to said machine for urging said arm together with said idler sprocket in [a] the take up direction.

2. In a mining machine of the type having a pair of boring arms arranged to cut contiguous bores [in a seam ofcoal or the-like], at least one retractable cutter chain guide and an endless cutter chain guided thereby for cutting a cusp remaining from, the action of said boring arms,'and a driving sprocket for said cutter chain, the improvement in such mining machine which comprises: means for taking'up [the]slack in said cutter chain occasioned by movementof-said' cutter chain guide to retracted position comprising an idler sprocket, an arm supporting said idler sprocket and mounted for swinging movement[, said arm having its] about a center of swing ing movement corresponding to the center of rotation of i said driving sprocket,.a guide upon said arm, said guide having an'arcuate surface substantially coincident withdirection.

3';In a mining machine of the type having a pair of boring arms arranged to cut contiguous bores, at least one retractable cutter chain guideand an endless cutter chain guided thereby for cutting a cusp remaining fromthe action of said boring arms, and a drive means for said cutter chain, the improvement in such mining machinewhich comprises: means swingably movably supported by the mining machine for taking up slack in said cutter chain occasioned by movement of said cutter chain 1 guide, said means including an arcuate surface substantially coincident with the swinging movement of the means, and other means for enabling and urging said first mentioned means to move in a direction totake up slack in said cutter chain, said other means including flexible means secured to said first mentioned means and disposed along said arcuate surface.

4. In a mining machine of the type having a pair of boring arms arranged to cut contiguous bores, at least one retractable cutter chain guide and an endless cutter chain guided thereby for cutting a cusp remaining from theiaction of'saidboring-arms; and a drive, means for said cutter chain, the improvement in such mining machine which comprises: means fortaking up slack in said cutter chain occasioned by'movement of said cutter chain guide to retracted position, said means including an arm supporting anidler-,member-and mounted for swinging movement on said mining machine, an arcuate guide surface on said arm substantially coincident with the swinging movement of the idler sprocket, and means including flexible means secured to said arm and disposed along the arcuate guide surface for urging said arm and idler member to move in a direction to take up slack in said cutter chain.

5. In a mining machine of the type having a pair of boring arms arranged to cut contiguous bores, at least one retractable cutter chain guide and an endless cutter chain guided thereby for cutting a cusp remaining from the action of said boring arms, and a driving sprocket for said cutter chain, the improvement in such minin'g machine which comprises: means for taking up slack and maintaining the proper tension in said cutter chain during movement of said cutter chain guide to retracted position, said means including an idler sprocket, an arm supporting said idler sprocket and pivotally mounted on said mining machine for swinging movement about a center of swinging movement corresponding to the center of rotation of said driving sprocket, a guide means on said arm having an arcuate surface substantially coincident with the swinging movement of the idler sprocket about said driving sprocket, flexible means secured to said arm and disposed along said arcuate surface for enabling the arm to move in a direction to take up slack in said cutter chain, and resilient means connected to said flexible means for urging said arm in the take-up direction to maintain the proper tension on the cutter chain.

References Cited in the file of this patent or the original patent UNITED STATES PATENTS Coal Age, May 13, 1926, pp. 667-670. Mining Congress Journal, October 1938, pp. 44 and 70. 

